Today miniature motors are applied in connection with different servo devices. In the automobile industry there are many applications of such servo devices, e.g. for opening and closing the windows or also for actuating a central locking device. The miniature motor or even several miniature motors have to be connected in the designated way with conductor tracks of a printed-circuit board or the like.
Originally, each motor was provided with a cable connection and the cable was connected with the conductor tracks of the printed-circuit board by plugging or soldering it. Attempts have also been made to connect contact sheets of the motor with flat plugs. These connections are expensive and time consuming since they have to be realized manually. Furthermore it is often undesirable to lay cables in the housing of the device because the cable can hinder the motion of the moving components. This applies especially when the device provided with one or more motors is exposed to vibrations, as is always the case in automobiles.
In another known version, such miniature motors are provided with slide connectors which protrude from the motor like the contact sheets do. These slide connectors are pushed into the openings of the conductor tracks and soldered directly to them. Although in this case no cable is involved, the miniature motors must have a precisely defined position in relation to the printed-circuit board or the conductor tracks in question. This defined position often does not correspond to the desired mounting position of the motor. This is especially true when the motor is not provided with a circular, but an oval or similar non circular housing. Furthermore the layout of the conductor tracks depends on the conformation of the motor. Modifications of the motor generally leads to a corresponding modification of the conductor tracks. This is time consuming and usually also very expensive.
The object of the present invention is therefore to develop the device mentioned at the beginning in such a way, that the motor can be mounted simply and quickly despite the absence of a cable connection and that small modifications of the motor do not involve any or at least any important adaptation to the connection of the printed-circuit board.
This object is achieved according to the present invention by putting the adapter between the end pieces of the conductor tracks and sockets of the motor. This arrangement provides for an electrically conductive connection between the motor and the conductor tracks and permits the quick adaptation to a slightly modified motor and/or modified end pieces of the conductor tracks. In addition to this, the connection of the motor with the adapter as well as the connection of the adapter with the end pieces of the conductor tracks is pluggable, so that cables are no longer necessary. The respective plug-in connections can be designed as already known. Therefore the miniature motor, e.g. coupled with the adapter, can be connected easily, quickly and safely with the end pieces of the conductor tracks, or in the specific case, with the central locking device, all prerequisites for an automatic assembly being given.
In another improvement of the present invention, the ends of the electrically conductive elements close to the motor are formed as plug pins which are retained in the sockets of the miniature motor in a clamped way. In this case the sockets have a flat plug-in opening in which the electrically conductive elements are plugged in an elastically clamped manner.
In another aspect of the present invention, the lateral distance of the ends of the electrically conductive elements close to the motor corresponds to the lateral distance of the sockets of the miniature motor so that both can be coupled by a linear motion and at the same time be connected in an electrically conductive way.
For reasons of cost and weight, the material thickness of the electrically conductive elements should be as small as possible. Stamped parts, however, must present a minimum thickness because of the stamping procedure. If the sockets after a modification of the miniature motor are provided with somewhat wider insertion slots for the electrically conductive elements, it may be possible that a tight fit of the electrically conductive elements in the sockets can no longer be ensured. In another embodiment of the present invention, an improvement is achieved in that the flat sides of the electrically conductive elements are parallel and each one shows a depression, particularly extending in the plug-in direction, which leads to enlarged ends of these electrically conductive elements to be inserted so that, at least in case of elastically expanding sockets, also small dimensional tolerances near the sockets can be compensated within certain limits.
The depressions of the two electrically conductive elements are directed towards each other in a particularly preferred manner. Since the form of the two electrically conductive elements is, apart from that, essentially similar, the different position of the depressions with regard to their flat sides provides for a certain identification which permits an automatic sorting. This is the prerequisite for an automatic or at least semi-automatic assembly. As for the rest, the electrically conductive elements can be retained in the base member of their adapter in one of the known ways, e.g. by jamming or by extrusion if the adapter, as foreseen in the present embodiment, is made of plastic material.
Preferably, the electrically conductive elements have an essentially angular shape. This means that when the electrically conductive elements abut loosely on a surface, one leg is parallel to the one of the other electrically conductive elements and their depressions point upwards, the other leg points into the opposite direction. This can be exploited for the identification of the single parts.
As already mentioned, the electrically conductive elements can be plugged into the base member or extruded with its material. In a variant of the present invention, preferred in this regard, clamping engagement is easily achieved by the depression, nipple provided the insertion slot or the material in this area is sufficiently yielding so that the depression or nipple can penetrate to some extent. A favorable variant is also to clamp the electrically conductive element by means of a snap connection in which the nipple snaps in behind a projection or undercut.
As already mentioned, the adapter and the end parts of the conductor track can be connected in a pluggable manner. In to ensure that this plug-in connection is vibration proof and to secure it, it is advisable to make each end piece of the conductor track engage between two fork prongs on the leg of the angle which is remote from the motor. The length of the parallel part of the fork prongs and therefore the constant width of the insertion slot corresponds to the width of the conductor track.
A particularly preferred variant of the present invention ensures that the unit consisting of the adapter and the miniature motor can be slipped onto the end pieces of the conductor track by a simple linear movement which permits a fully automatic assembly and excludes wrong electrical connections in each of the two connecting points.
In order to ensure a safe electrical connection between the end pieces of the conductor track and the adapter or its electrically conductive elements, an enlargement at the insertion end of each end piece of the conductor track is provided for, in particular a depression extending in the plug-in direction, which is associated with the space between the parallel parts of the fork prongs. By this it is also possible to achieve a tight mechanical connection which certainly leads to a high electrical safety of these connecting points.
Developments being of particular advantage to the fully automatic connection of the adapter or the unit consisting of adapter and miniature motor with the end pieces of the conductor track, are described. First of all, the insertion slopes permit a safe connection between the adapter and the end pieces of the conductor track even if there is a slight deviation from the correct position. By means of the insertion slopes, they are introduced safely into the insertion slots on the inside of which are positioned the forks of the two electrically conducting elements which are coupled mechanically and in an electrically conductive manner to the end pieces of the conductor track when the adapter is slipped onto these end pieces.